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Message-ID: <66729683-32ad-4000-b9be-001cd5631b97@collabora.com>
Date: Fri, 19 Apr 2024 09:44:53 +0200
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Subject: Re: [PATCH v2 1/3] dt-bindings: display: mediatek: Add OF graph
 support for board path
To: Rob Herring <robh@kernel.org>
Cc: chunkuang.hu@kernel.org, krzysztof.kozlowski+dt@linaro.org,
 conor+dt@kernel.org, p.zabel@pengutronix.de, airlied@gmail.com,
 daniel@ffwll.ch, maarten.lankhorst@linux.intel.com, mripard@kernel.org,
 tzimmermann@suse.de, matthias.bgg@gmail.com, shawn.sung@mediatek.com,
 yu-chang.lee@mediatek.com, ck.hu@mediatek.com, jitao.shi@mediatek.com,
 devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
 dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org,
 linux-arm-kernel@lists.infradead.org, wenst@chromium.org,
 kernel@collabora.com
References: <20240409120211.321153-1-angelogioacchino.delregno@collabora.com>
 <20240409120211.321153-2-angelogioacchino.delregno@collabora.com>
 <20240410190335.GA890682-robh@kernel.org>
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
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In-Reply-To: <20240410190335.GA890682-robh@kernel.org>
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Il 10/04/24 21:03, Rob Herring ha scritto:
> On Tue, Apr 09, 2024 at 02:02:09PM +0200, AngeloGioacchino Del Regno wrote:
>> The display IPs in MediaTek SoCs support being interconnected with
>> different instances of DDP IPs (for example, merge0 or merge1) and/or
>> with different DDP IPs (for example, rdma can be connected with either
>> color, dpi, dsi, merge, etc), forming a full Display Data Path that
>> ends with an actual display.
>>
>> The final display pipeline is effectively board specific, as it does
>> depend on the display that is attached to it, and eventually on the
>> sensors supported by the board (for example, Adaptive Ambient Light
>> would need an Ambient Light Sensor, otherwise it's pointless!), other
>> than the output type.
>>
>> Add support for OF graphs to most of the MediaTek DDP (display) bindings
>> to add flexibility to build custom hardware paths, hence enabling board
>> specific configuration of the display pipeline and allowing to finally
>> migrate away from using hardcoded paths.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> ---
>>   .../display/mediatek/mediatek,aal.yaml        | 40 +++++++++++++++++++
>>   .../display/mediatek/mediatek,ccorr.yaml      | 21 ++++++++++
>>   .../display/mediatek/mediatek,color.yaml      | 22 ++++++++++
>>   .../display/mediatek/mediatek,dither.yaml     | 22 ++++++++++
>>   .../display/mediatek/mediatek,dpi.yaml        | 25 +++++++++++-
>>   .../display/mediatek/mediatek,dsc.yaml        | 24 +++++++++++
>>   .../display/mediatek/mediatek,dsi.yaml        | 27 ++++++++++++-
>>   .../display/mediatek/mediatek,ethdr.yaml      | 22 ++++++++++
>>   .../display/mediatek/mediatek,gamma.yaml      | 19 +++++++++
>>   .../display/mediatek/mediatek,merge.yaml      | 23 +++++++++++
>>   .../display/mediatek/mediatek,od.yaml         | 22 ++++++++++
>>   .../display/mediatek/mediatek,ovl-2l.yaml     | 22 ++++++++++
>>   .../display/mediatek/mediatek,ovl.yaml        | 22 ++++++++++
>>   .../display/mediatek/mediatek,postmask.yaml   | 21 ++++++++++
>>   .../display/mediatek/mediatek,rdma.yaml       | 22 ++++++++++
>>   .../display/mediatek/mediatek,ufoe.yaml       | 21 ++++++++++
>>   16 files changed, 372 insertions(+), 3 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml
>> index b4c28e96dd55..623cf7e37fe3 100644
>> --- a/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml
>> +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml
>> @@ -61,6 +61,27 @@ properties:
>>       $ref: /schemas/types.yaml#/definitions/phandle-array
>>       maxItems: 1
>>   
>> +  ports:
>> +    $ref: /schemas/graph.yaml#/properties/ports
>> +    description:
>> +      Input and output ports can have multiple endpoints, each of those
>> +      connects to either the primary, secondary, etc, display pipeline.
>> +
>> +    properties:
>> +      port@0:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description: AAL input port
>> +
>> +      port@1:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description:
>> +          AAL output to the next component's input, for example could be one
>> +          of many gamma, overdrive or other blocks.
>> +
>> +    required:
>> +      - port@0
>> +      - port@1
>> +
>>   required:
>>     - compatible
>>     - reg
>> @@ -88,5 +109,24 @@ examples:
>>              power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
>>              clocks = <&mmsys CLK_MM_DISP_AAL>;
>>              mediatek,gce-client-reg = <&gce SUBSYS_1401XXXX 0x5000 0x1000>;
>> +
>> +           ports {
>> +               #address-cells = <1>;
>> +               #size-cells = <0>;
>> +
>> +               port@0 {
>> +                   reg = <0>;
>> +                   aal0_in: endpoint {
>> +                       remote-endpoint = <&ccorr0_out>;
>> +                   };
>> +               };
>> +
>> +               port@1 {
>> +                   reg = <1>;
>> +                   aal0_out: endpoint {
>> +                       remote-endpoint = <&gamma0_in>;
>> +                   };
>> +               };
>> +           };
>>          };
>>       };
>> diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml
>> index 8c2a737237f2..71ea277a5d8e 100644
>> --- a/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml
>> +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml
>> @@ -54,6 +54,27 @@ properties:
>>       $ref: /schemas/types.yaml#/definitions/phandle-array
>>       maxItems: 1
>>   
>> +  ports:
>> +    $ref: /schemas/graph.yaml#/properties/ports
>> +    description:
>> +      Input and output ports can have multiple endpoints, each of those
>> +      connects to either the primary, secondary, etc, display pipeline.
>> +
>> +    properties:
>> +      port@0:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description: CCORR input port
>> +
>> +      port@1:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description:
>> +          CCORR output to the input of the next desired component in the
>> +          display pipeline, usually only one of the available AAL blocks.
>> +
>> +    required:
>> +      - port@0
>> +      - port@1
>> +
>>   required:
>>     - compatible
>>     - reg
>> diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml
>> index b886ca0d89ea..61d040a10c08 100644
>> --- a/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml
>> +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml
>> @@ -64,6 +64,28 @@ properties:
>>       $ref: /schemas/types.yaml#/definitions/phandle-array
>>       maxItems: 1
>>   
>> +  ports:
>> +    $ref: /schemas/graph.yaml#/properties/ports
>> +    description:
>> +      Input and output ports can have multiple endpoints, each of those
>> +      connects to either the primary, secondary, etc, display pipeline.
>> +
>> +    properties:
>> +      port@0:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description: COLOR input port
>> +
>> +      port@1:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description:
>> +          COLOR output to the input of the next desired component in the
>> +          display pipeline, for example one of the available CCORR or AAL
>> +          blocks.
>> +
>> +    required:
>> +      - port@0
>> +      - port@1
>> +
>>   required:
>>     - compatible
>>     - reg
>> diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml
>> index 1588b3f7cec7..3d4ab3f86294 100644
>> --- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml
>> +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml
>> @@ -55,6 +55,28 @@ properties:
>>       $ref: /schemas/types.yaml#/definitions/phandle-array
>>       maxItems: 1
>>   
>> +  ports:
>> +    $ref: /schemas/graph.yaml#/properties/ports
>> +    description:
>> +      Input and output ports can have multiple endpoints, each of those
>> +      connects to either the primary, secondary, etc, display pipeline.
>> +
>> +    properties:
>> +      port@0:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description: DITHER input, usually from a POSTMASK or GAMMA block.
>> +
>> +      port@1:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description:
>> +          DITHER output to the input of the next desired component in the
>> +          display pipeline, for example one of the available DSC compressors,
>> +          DP_INTF, DSI, LVDS or others.
>> +
>> +    required:
>> +      - port@0
>> +      - port@1
>> +
>>   required:
>>     - compatible
>>     - reg
>> diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml
>> index 803c00f26206..6607cb1c6e0a 100644
>> --- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml
>> +++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml
>> @@ -64,13 +64,34 @@ properties:
>>         Output port node. This port should be connected to the input port of an
>>         attached HDMI, LVDS or DisplayPort encoder chip.
>>   
>> +  ports:
>> +    $ref: /schemas/graph.yaml#/properties/ports
>> +
>> +    properties:
>> +      port@0:
>> +        $ref: /schemas/graph.yaml#/properties/port
>> +        description: DPI input port
> 
> Strictly speaking, 'port' is equivalent to 'port@0', so it is already
> defined to be the output path. It is a little odd for the input to be
> port@1, but that is why we define the numbering.
> 
> Same comment applies to DSI.
> 
> Rob

Sorry Rob, but I think I didn't understand your comment here.. because the
input is port@0, not port@1...

DPI/DSI/other components IN  -> port@0
DPI/DSI/other components OUT -> port@1

Cheers,
Angelo